The present invention relates to a combine harvester with a threshing unit and a driver assistance system which controls the threshing unit, the driver assistance system including a memory for storing data, and a computing unit for processing the data stored in the memory.
Combine harvesters are used for mowing and threshing of grain. The threshing is carried out by a threshing unit, which obtains grain from the crop picked up by the combine harvester using a header. The grain, after threshing, separation and subsequent cleaning, is fed to a grain tank. The chaff and the straw, for example, remain as further components of the crop and are either spread onto the field or, in the case of straw, can be set down as swath, e.g., to be subsequently picked up by a baler. Here and in the following, the term “crop” is intended to mean the entirety of the crop stream picked up by the threshing unit, i.e., including the grains that have not yet been obtained as grain from the crop, and the grains that may remain in the crop stream as a loss and that may be deposited with the straw.
In the threshing unit, the grain is rubbed, i.e., threshed, out of the straw by a processing, which comprises rolling, in principle, and is separated from the remaining crop stream, so that it can be fed directly to the cleaning system. The remaining crop stream is then fed to the separation area in which the remaining grain is separated from the crop stream, e.g., by a straw-walker system and is then likewise fed to the cleaning system.
There is an entire series of criteria, on the basis of which the quality of the threshing process can be evaluated. First, preferably all the grain should be removed from the crop stream and fed to the grain tank, specifically with as few broken kernels as possible, and with a minimal portion of material other than grain. Secondly, the straw also should not be damaged and, e.g., cut up, to such an extent that subsequent utilization is adversely affected. Third, the time required for the processing of a field should be short and the associated fuel consumption should be kept as low as possible. Further quality criteria are conceivable. Depending on the overall situation, in particular on the particular basic economic conditions, different quality criteria are paramount, which criteria collectively form a harvesting-process strategy for carrying out the harvesting process.
In order for the aforementioned quality criteria to be met, the threshing unit must be controlled in a certain manner, wherein this manner depends not only on the special quality criteria, but also on different conditions of the environment, of the combine harvester and, in particular, of the threshing unit itself, and on the type and composition of the crop. The prioritization of one quality criterion is usually a disadvantage for another quality criterion.
From the prior art and, in particular, EP 1 731 017 B2, it is known to provide a special control process in a control device for optimizing the threshing unit, i.e., the threshing-unit optimization process. When this control process is activated, it sets “optimal” threshing-unit settings on the threshing unit and then shuts off. This threshing-unit optimization process always runs in the same manner and, in particular, using the same settings. The activation of the threshing-unit optimization process furthermore shuts off a regulation process, which may be running at the time, for the ground speed of the combine harvester, so that said combine harvester cannot run simultaneously.
Moreover, DE 10 2009 009 767 A1, discloses a combine harvester comprising a driver assistance system, which driver assistance system measures different variables (e.g., speed, concave width, grain losses) on the combine harvester and checks them to determine whether they pass into a critical value range or exceed or undershoot critical limit values. If this situation occurs, the driver assistance system interactively communicates with the driver by proposing, to the driver, measures to take during the control of the threshing unit that are intended for moving out of the critical value range. The driver can then accept or reject these proposals, wherein, in a subsequent step, alternative proposals may be made to the driver, or the driver can specify the proposed measures more precisely by an entry.
The disadvantage of such prior art is that the driver assistance system determines the aforementioned measures on the basis of a database having expert knowledge stored therein, which expert system is always associated with complex hardware and considerable administration effort.